The correct option is D 1.42 atm
6.023×1023 Oxygen Molecules = 1 mole
6.023×1022 Oxygen Molecules =1×6.023×10226.023×1023 = 0.1 mole
Hence, no. of moles of Oxygen Molecules in 150ml Vessel = 0.1
We know, PV = n RT or, P = nRTV
⇒P=0.1×082×2601.5=1.42atm